1. Field of the Invention
The present invention relates to vibration dampening mechanisms and, more particularly, to vibration dampeners for airboat propulsion systems.
2. Description of Related Art
Airboats are designed to be driven at high speeds over water and land and to have a high degree of mobility. Either an aircraft or automobile engine may be used to drive either a single propeller or a pair of counter-rotating propellers at rotational velocities in the range of 1000-5000 rpm. The transmissions employed may be either belt-driven or gear-based.
A typical structure for an airboat propulsion system comprises an engine, to which is affixed a flywheel that is rotated by the crankshaft when the engine is running. The flywheel in airboats previously known in the art is then affixed to the fore end of the drive shaft, which extends in an aft direction from the flywheel and imparts rotational motion to the transmission. Normal engine vibration, which is in part caused by the nature of the reciprocal engine, is also transmitted along the drive shaft, and causes wear on the transmission elements and other downstream components, decreasing their useful life. It would thus be desirable to damp such vibration downstream of the engine. Such vibration also increases the noise produced by airboats, which is a significant detriment to their use.